Update function deploy handler contract text to fetch-style

[etbyrd]

Summary

The Functions tag description and the createFunction operation description in the OpenAPI spec said the handler "exports a default async function receiving the `email.received` event." That described a different runtime contract than the one Functions actually run, and that mismatch surfaced as ambiguity for anyone reading the manifest while writing a handler.

The real contract is a Workers-style fetch handler:

• Default export is an object with an async `fetch(request, env)` method.
• The gateway HMAC-verifies the inbound POST against the org's webhook secret before invoking `fetch`.
• The request body parses to an `email.received` event (`EmailReceivedEvent`).

This is what the scaffolder writes (`cli-node/src/oclif/commands/functions-init.ts`), what the `CreateFunctionInput.code` schema description already says (`Must export a default { async fetch(req, env, ctx) { ... } } object.`), and what the public docs describe. The Functions tag and createFunction `description` blocks were the stale outliers.

This PR updates the OpenAPI source (`openapi/primitive-api.yaml`) in two places and regenerates the downstream artifacts (`openapi/primitive-api.codegen.json`, Node SDK generated openapi + operations + sdk.gen, Python generated client, Go generated client/handlers/server).

No code paths change; this is documentation/manifest text only.

Test plan

• `pnpm --dir sdk-node lint`
• `pnpm --dir sdk-node typecheck`
• `pnpm --dir cli-node lint`
• `pnpm --dir cli-node typecheck`
• `pnpm --dir sdk-node generate` produces the committed artifacts (no drift)
• No remaining occurrences of the stale phrasing across the repo

[greptile-apps]

Greptile Summary

This PR corrects stale documentation in the OpenAPI spec and all generated downstream artifacts — no runtime behaviour changes. The Functions tag description and createFunction operation description previously described an incorrect contract (default async function receiving email.received) and are updated to match the actual Workers-style fetch handler contract.

• openapi/primitive-api.yaml is the only hand-edited file; all other changes are regenerated artifacts that faithfully reflect the YAML update.
• The new text is consistent across the YAML source, codegen JSON, Go SDK (client/handlers/server/unimplemented), Node SDK (sdk.gen, openapi.generated, operations.generated), and Python client (all four function variants).

Confidence Score: 5/5

Safe to merge — every changed line is documentation text with no effect on runtime behaviour.

All ten files are either the OpenAPI source or auto-generated artifacts. The only substantive edit is correcting two description strings in primitive-api.yaml; the remaining nine files are regenerated output that mirrors those strings exactly. No code paths, schemas, types, or logic are touched.

No files require special attention.

Important Files Changed

Filename	Overview
openapi/primitive-api.yaml	Source of truth: updates Functions tag description and createFunction operation description to reflect the Workers-style fetch handler contract
openapi/primitive-api.codegen.json	Generated codegen JSON mirrors YAML changes; description strings match the updated source exactly
sdk-go/api/oas_client_gen.go	Generated Go client: doc comment on CreateFunction updated to match new contract; no logic changes
sdk-go/api/oas_handlers_gen.go	Generated Go handlers: doc comment on handleCreateFunctionRequest updated; no logic changes
sdk-go/api/oas_server_gen.go	Generated Go server interface: doc comment on CreateFunction updated; no logic changes
sdk-go/api/oas_unimplemented_gen.go	Generated Go unimplemented handler: doc comment updated; no logic changes
sdk-node/src/api/generated/sdk.gen.ts	Generated Node SDK: JSDoc comment on createFunction updated; no logic changes
sdk-node/src/openapi/openapi.generated.ts	Generated Node OpenAPI document object: both Functions tag description and createFunction description updated; no logic changes
sdk-node/src/openapi/operations.generated.ts	Generated Node operation manifest: createFunction description field updated; no logic changes
sdk-python/src/primitive/api/api/functions/create_function.py	Generated Python client: docstrings updated consistently across all four variants (sync_detailed, sync, asyncio_detailed, asyncio); no logic changes

_{Reviews (2): Last reviewed commit: "Merge branch 'main' into update-function..." | Re-trigger Greptile}